[PATCH bpf-next v6 0/2] bpftool: fix batch file handling issues

[Yuan Chen <chenyuan_fl@163.com>]

This series fixes two remaining issues in bpftool's batch file handling
(the double-close fix from v5 has been applied upstream and is no
longer part of this series):

 1. do_batch() reports a spurious read failure because a stale errno
    left by a previously executed command is checked after the read
    loop instead of the outcome of the last fgets() call.
 2. a line longer than the batch buffer that contains a '#' within the
    buffered prefix bypasses the line length check: the comment
    stripping truncates the buffer before the length is checked, so the
    unread remainder of the line is parsed and executed as a separate
    command on the next loop iteration. Continuation lines are affected
    the same way, bypassing the "command is too long" check.

Many thanks to Andrii Nakryiko for the review: patch 1 now clears errno
before each fgets() call instead of tracking the too-long-line case
with an explicit flag, and patch 2 moves the line-length checks before
the comment stripping instead of detecting truncated reads with
memchr()/feof().

Changes in v6:
  - drop the double-close patch, which has been applied upstream; the
    series is now two patches
  - "fix spurious batch file read error": clear errno before each
    fgets() call, and drop the explicit line_too_long flag and the
    ferror() check (reviewer feedback)
  - "Fix bypass of the batch line length check by comments": move the
    line-length checks before the comment stripping, dropping the
    memchr()/feof() truncation detection (reviewer feedback)

Yuan Chen (2):
  bpftool: fix spurious batch file read error
  bpftool: Fix bypass of the batch line length check by comments

 tools/bpf/bpftool/main.c | 30 ++++++++++++------------------
 1 file changed, 12 insertions(+), 18 deletions(-)